Microimaging schemes based upon photoreactions of chalcogen compounds, for example, benzyl diselenide, and photoreactions of chalcogen compounds with mercury compounds have been proposed which possess desirable features which render their use advantageous in many situations. However, these imaging systems based upon the photochemistry of chalcogen compounds have the disadvantage of instability in that they are not easily fixed.
It is known that the direct photochemistry of benzyl diselenide (BDS) with ultraviolet light results in the formation of dibenzylselenide (DBS) and selenium. This is shown in equation 1 along with the back reaction: EQU (R Se).sub.2 .gamma..sup.hr R.sub.2 Se + Se.degree. (1)
It is further known that triphenylphosphine (TPP) will react with elemental selenium and with selenium radicals to produce triphenylphosphineselenide, a colorless product. In solution, this leads to increases in the quantum yield for the disappearance of benzyl diselenide presumably via secondary free radical reactions. This reaction occurs as well in solid films and forms a latent image of triphenylphosphineselenide, which if developed would provide additional contrast above and beyond that obtained by direct photolysis in the absence of this scavenging reagent.
An object of the present invention is to provide an improved process for the manufacture of microimaging film structures.
A further object is to provide a microimaging film with gain.
An additional object is to provide a microimaging film with both high contrast and high resolution.
Another object is to provide a stable microimaging film, that is one that may be fixed to preserve the image contrast, and prevent unwanted and undesirable subsequent fogging and reimaging.